Electrical subassemblies are often connected to one another via card edge connectors, of which there are two types. A female edge connector comprises one or more slots. Electrical contacts interior to the one or more slots terminate exterior to the edge connector in a plurality of solder tails (or any other suitable contact means). A male edge connector comprises a plurality of edge connector traces which are formed on, and arranged perpendicularly to, the edge of a PC board. In order to connect two electrical subassemblies comprising edge connectors, a male edge connector of a first subassembly is inserted into a female edge connector of a second subassembly. Intel.RTM.'s Pentium.RTM. II microprocessor is an example of a subassembly comprising a male edge connector. The male edge connector of a Pentium.RTM. II microprocessor comprises 242 edge connector traces arranged on opposite sides of two tabs of a PC (printed circuit) board to which the components of the Pentium.RTM. II microprocessor are electrically coupled. The Pentium.RTM. II edge connector is commonly known as a Slot 1 edge connector.
After proper operation of an electrical subassembly has been verified, it is usually necessary to evaluate the subassembly's interaction with one or more other subassemblies (e.g., a microprocessor's interaction with an external chip set, RAM, peripheral interfaces, and other components connected to a computer's motherboard). This is typically accomplished by inserting an edge connector interposing probe between the two subassemblies.
An edge connector interposing probe is a device which forms a series bridge between the edge connectors of two subassemblies. Signals passing through the bridge are "probed". That is, the signals are sampled and routed to test equipment such as a logic analyzer.
However, currently available edge connector interposing probes pose a number of problems. First, they add a significant series length to the path of a signal being probed. This added length can cause unwanted signal delay, which in turn can lead to induced performance losses and even errors in a device under test. Second, currently available edge connector interposing probes tend to induce a lot of "crosstalk" (or noise) into signals being monitored. If there is too much crosstalk, signals received by test equipment may be inaccurate representations of the signals transmitted between the two subassemblies, and/or two subassemblies connected via the interposing probe may fail to communicate as intended. Finally, currently available edge connector interposing probes can place substantial loads on signal routes being probed--further disturbing the proper functioning of a device under test.